Intercommunicating lockout telephone system.



F. W. ADSIT.

INTERCONIMUNICATING LOCK-OUT TELEPHONE SYSTEM. APPLICATION FILED MAY 24. 1915. RENEWED res. 13.1917.

1,228,634., Patented J 11116 5, 1917.

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FRANK W. ADSIT, OF MINNEAPOLIS, MINNESQ'IA.

INTEECO M MUNICATING LOCKOUT TELEPHONE To all whom it may concern.

Be it known that I, FRANK lV. Ansrr, a citizen of the United States, residing at Minneapolis, in the county ofl-lennepin, State of Minnesota, have invented new and useful Improvements in Inter-communicating Lockout Telephone Systems, of which the following is a specification.

My invention relates moreparticularly to providing means whereby one subscriber on a telephone party line may call any other subscriber on that line at will, and also provides means whereby the conversation between the two parties is private, the remaining parties on the line being locked out, and provides further means whereby the system may be automatically restored to normal without action on the part of the subscriber other than hanging his receiver on the switch-hook.

The drawing discloses three magneto type of telephones equipped with my invention and denoted by the letters A, B and C. The circuits at the three stationsare identical and for convenient reference the wires and parts of station A are numbered, and corresponding elements at B and O are denoted by the same numbers where referred to'in this specification with the symbol added at station B and'the symbol added at station C.

The arrangement of circuits and apparatus in my invention is such that it may be embodied in the form of an attachment that can be added to the common type of magneto telephone and does not necessarily mean a complete instrument including the ordinary telephone apparatus.

The three subscribers sets, A, B and G disclosed in the drawing are connected to.

the metallic line denoted by numerals 1, and 2 and there is further provided a ground connection 3, 3, 3 which may be a connection to the earth or a third wire may be used and the earth connection dispensed with.

If party A wishes to talk with party B, he will first set the dial 4 to correspond with the number of the telephone of subscriber B and then turn the crank of the magneto 5, which is adapted to supply alternating current, the result being then a flow of alternating current from the magneto 5 as follows:

Wires 6 and 7 to shaft 8, contact 9, Wire 1 l wires 12 and 13 to the line W re Specification of Letters Patent.

Patented June 5, 1917.

Renewed February 13, 1917, Serial No. 148,901.

2, wire 141, to the other side of the magneto 5. The alternating current flowing through the coil 11 pulls the armature 15 downward, freeing the catch 16 and operating the bank of springs associated therewith. The continuation of the act of turning the magneto crank now sends current through wire 17, contact 18, wire 19, contact 20, wires 21 and 22, to the line wire 1, and the other side of the magneto 5 being connected by wire 11 to the side 2 of the line, magneto, current is supplied to whatever apparatus is then bridged to these wires at any instrument on the line.

Continuing with the circuit at A, the coils are connected to the line wire 2 by wires 13, 12, 9,3 and 24:, and to the line wire 1 by wires 25, 26, 27 and 22, hence this coil will be actuated by the alternating current from the magneto and by means of the actuating pawl 28 and retaining pawl 29 will turn the ratchet wheel 30 in a clockwise direction.

\ As coils 23 and 23 are connected similarly to the line wires 1 and 2, the ratchet wheels 30 and 30 will be operated in a similar manner.

As the ratchet wheels 30, 30' and 30" are all stepped around by the alternating current from common source, namely the magneto 5,"their motion will be synchronous.-

by the ratchet wheels 30, 30," and 30' re spectively, carry contact pointers 31, 31 and 31 respectively, which are insulated from their shafts by the bushings 32, 32 and 32 respectively.

These respective contact pointers are adapted to make contact with the springs 33, 33 and 33 respectively, as they are rotated, and the angular position of the pointers 31, 31 and 31 is in eachcase de' termined by the number given to that'particular telephone, the adjustment being made by means of the screws 34:, 3-1 and 341 respectively and each of the pointers will therefore make its contact with its respective spring at a different time in the turning of the synchronously moving Wheels 30, 30 and 30".

As the positioning of the pointers 31, 31 and 31" correspond to the number of the telephone in each instance, when the dial t at station A is set to correspond to subscriber B, the contact spring 35, has been The shafts 8, 8 and 8, which are driven I by this act positioned so that the pointer 86 at station A will make contact with the spring 85 at the same time that contact pointer 81 makes contact with the spring 88 at station B.

The contact pointers 86, 86 and 86 are insulated from the shafts 8, 8 and 8 re spectively by the bushings 87, 87 and 87 respectively.

When the pointer 86 at station A makes contact with the spring 85, and the pointer 81 at station E makes contact with the spring 88, a circuit for the magneto current is established as follows:

Magneto 5, wire 14, line wire 2, wires 18, 89, coil 40, wire 41, contact 42, wire 48, spring 88, contact pointer 81, spring 44, wires 45, 46, ground 8, through the ground to the ground at 8 at station A, wires 46, 47, spring 48, contact pointer 36, spring 85, spring 49, wires 50, 26, 27, 21, contact 20, wire 19, contact 18, wire 17, contact 51 which is closed by the act of turning the magneto crank, as in common types of mag netos, to the other side of the magneto 5.

The magneto current passing through the coil 40 pulls up the armature 52 releasing the latch 89 and operates the bank of springs associated therewith. The crank of the magneto 5 still turning, the ratchet wheels 80, 80 and 80 are still stepping synchronously until the stops 58, 58 and 58 make contact with the contact points 54, 54 and 54, respectively, which stops further rotation of the wheels and also establishes a circuit as follows:

Magneto 5, wires 6 and 7, shaft 8, stop 58, contact point 54, Wire 55, contact 96, Wire 41, coil 40, wires 89, 18, line wire 2, wire 14,

to the other side of the magneto 5, operating the armature 52 releasing the latch 89, and through this the bank of springs associated therewith.

This final operation of the bank of springs associated with coil 40 establishes a circuit as follows:

Magneto 5, Wires 6, 56, contact 57 wires 58, 59, switch hook contact 60, ringer 61 to the ground at 8, through the ground to the ground at 8' at station B, ringer 61, switch hook contact wires 59', 58, contact 57,

wires 56, 6, contact 88, (which short-circuits the magneto Winding when the crank is not being turned), wire 14 line wire 2, wire 14 to the other side of the magneto 5, thus ringing both ringers 61 and 61- in series over the line wire 2 and through the ground. As both bells are rung in series, when th party B'answers by removing the receiver 62 from the switch hook 68, the circuit is opened at the contact 60, and both ringers will be stopped from ringing; hence the party at A will know the party at B has answered, and will then remove'his own re- The secondary circuit at station, A. is as follows: secondary 71 of the induction coil, wire 72 to line wire 1; from the other side of the secondary 71 of the induction coil, wire 78, condenser 74, wire 75, receiver 62, wire 76, contact 77, switch hook 68, wires 58,

contact 57, wires 56, 6, contact (which now short-circuits the winding of the mag neto 5 as the crank is no longer being turned), wire 14 to the other side 2 of the line.

The secondary circuit of station E is identical, and the connection of the two circuits by the line wires 1 and 2 ompletes the tall ing circuit.

Referring now to circuit C, the only operation that has taken place has been the stepping of the wheel synchronously with the wheels 80 and 80, but, as the con tacts between pointer 81" and spring 88 were made at a time when no contact was made by contact pointer 86 and spring at station A, no coils received operating current except the coils 28 which are permanently bridged on theline wires 1 and 2, and serve to step around the wheel 80".

As the secondary of the talking set at station C terminates at the contact 57 which is open as the coil 40 has not been operated, that telephone is locked out, and a party at that station cannot hear any conversation going on over the line wires 1 and 2, nor can he, by talking into histransmitter, send any voice currents out on to that line.

Furthermore, the magneto circuit from contact 51", wire 17, contact 18", wire 19, is open at contact 20 and the magneto circuit from wire 6, wire 56 is opened at 57, and also from wires 6", 7 shaft 8 is open until stop 58 makes contact with 54.'- Thereafter as the circuit through wire 55" is open at contact 96 the subscribers generator at station C is also inoperative.

The description heretofore, together with the drawings, indicate that it is necessary to havethe contact at 9, 9' or 9 closed in order to secure control of the line, and as all of the ratchet wheels are stepped synchronously, the first step will break this contact in all instruments, but, at the station initiating the call, control of the line is given to that party through the operation of the bank of springs associated with the coil 11.

The system is restored to normal by bridg ing direct current of a proper ,polarity across the line wires 1 and 2, the current at station A flowing through the coil 23, which is permanently bridged on the line and whose action is polarized by the permanent magnet 97 in such direction that the contact '79 is closed, which places the coil across the line wires 1 and 2, the circuit being from line 1,"wires 22, 27, 81, coil 80, wire 82, contact-79 wires 83, 93, 12, 13, to the other side 2 of the line. The direct current which then flows through coil 80, pulls the armature 84 which is pivoted at 85 to- 'ard the coil 80, one end of'this lever lifting out the actuating pawl 2-8 and the retaining pawl 25), the other end of the lever through the insulating bar 9-l moving the main springs and 86 back to their normal position and allowing the armature 15 to be retractedv to its normal position by the spring 87; also through the means of the insulating bar 88 the main springs 89 and 90 are restored to their normal positions,

- allowing the armature 52 to be retracted by spring 91.

The action at stations B and C is the same and thus the bridging of direct battery of suitable voltage on the line wires 1 and 2, through any means, automatic or manual, serves to restore the system to its normal condition in readiness for another call.

The operation in practice is simple, positive and etiicient. It is only necessary for the subscriber to set his dial to the number of the party desired and turn the magnetocrank until his own bell rings, when, he knows the other partys bell is being rung, and continue his ringing until he knows, through the stopping of the ringing of his own bell that the other party has answered.

In a system using fifteen stations on a line, the entire act of selection up to the time when the called partys bell begins ringing, will not normally exceed three to four seconds.

While I have described and illustrated my invention with one particular circuit and arrangement of apparatus, I wish it understood that I do not confine myself to this particular arrangement of parts and circuit as described, as it is evident my invention may be applied in various manners within the scope of the following claims;

1. In an intercommunicating telephone lock-out system the combination of two subscribers stations, a pair of wires connecting said subscribers stations, a ground connection at each of said subscribers stations, means at each of said subscribers stations adapted to generate alternating current, means responsive to said alternating current at each subscribers station, a shaft at each subscribers station adapted to be rotated by said means responsive to said alternating current, a contact positioned near said shaft, means associated with said shaft adapted to close and open said contact during the rotation of said shaft, a second contact p0- sitioned near said shaft, a second means associated with said shaft adapted to close and open said second contact during the rotation of said shaft, and adjustable means adapted to vary the point in the rotation of said shaft at which said second contact is closed and opened.

In an intercommunicating telephone lock-out system the combination of two subscribers stations, a pair of wires connecting said subscribers stations, and the combination at each of said subscribers stations of an alternating current generator, a shaft, means responsive to alternating on "rent adapted to rotate said shaft, a permz'inently located contact point adjacent to said shaft,

a contact maker on said shaft adapted to make contact with said permanently located.

contact point during the rotation of said' shaft, a settable contact point positioned adjacent to said shaft, and a second contact maker on said shaft adapted to make contact with said settable contact point during the rotation of said shaft.

3. In an intercommunicating telephone lock-out system the combination of two subscribers stations, a pair of wires connecting said subscribers stations, the combination at each of said subscribers stations of an alternating current generator, a shaft, means responsive to alternating current adapted to rotate said shaft, a permanently located contact point adjacent to said shaft, a contact maker associated with said shaft and adapted to make and break contact with said permanently located contact point during the rotation of said shaft, a settable contact point positioned adjacent to said shaft, a second contact maker associated with said shaft adapted to make and break contact with said settable contact pointduring the rotation of said shaft, means adapted to limit the amount of rotation of said shaft, and a contact adapted to be closed when the rotation of said shaft is substantially completed.

4:. In an intercommunicating telephone lock-out system the combination of two subscribers stations, a pair of wires connecting said subscribers stations, and the combination at each of said subscribers stations of an alternating current generator, a shaft, means responsive to alternating current adapted to rotate said shaft, a permanently located contact point adjacent to said shaft, a contact maker associated with said shaft and adapted to make and break contact with said contact point during the rotation of said shaft, a settable contact point adjacent to said shaft, a second contact maker associated. with said shaft adapted to make contact lie with said settable contact point during the rotation of said shaft, and a normal contact adapted to be opened at the beginning of the rotation of said shaft.

5. In an intercommunicating telephone lockout system the combination of three subscribers stations, a pair of wires connecting said subscribers stations, and the combination at each of said subscribers stations of an alternating current generator, a shaft, means responsive to alternating current adapted torotate said shaft, a permanently located contact point adjacent to said shaft, a contact maker associated with said shaft adapted to make contact with said permanently located contact point during the rotation of said shaft, a settable contact point positioned adjacent to said shaft, a sec- 0nd contact maker associated with said shaft called, by alternating current from said alternating current generator of one of the other of said subscribers stations when it is calling through said settable contact at said subscribers station that is calling.

6. In an intercommunicating telephone lock-out system the combination of three subscribers stations, a pair of wires con necting said subscribers stations, aground connection at each of said subscribers stations, an alternating current generator, a shaft, means responsive to alternating current adapted to rotate said shaft, a permanently located contact point adjacent to said shaft, a contact maker associated with said shaft adapted to make contact with said permanently located contact point during the rotation of said shaft, a settable contact point adjacent to said shaft, a second contact maker associated with said shaft adaptfrom a circuit including said pair of wires Y connecting said subscribers stations to a circuit including one of said wires connecting i said subscribers stations and a ground connection.

- FRANK W. Ansrr.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

